This invention relates to mailing machines including a moistener assembly for wetting a gummed flap of an envelope. More particularly, this invention is directed to a stripper blade of the moistener assembly for separating the flap from a body of the envelope.
Mailing machines for processing envelopes are well known in the art. Various mailing machines are readily available from manufacturers such as Pitney Bowes Inc. of Stamford, Conn., USA and often include a variety of different modules, which automate the processes of producing envelopes. The typical mailing machine includes a variety of different modules or sub-systems where each module performs a different task on an envelope, such as: singulating (separating the envelopes one at a time from a stack of envelopes), weighing, moistening/sealing (wetting and closing the glued flap of an envelope), applying evidence of postage, accounting for postage used (performed by the postage meter), feeding roll tape or cut tape strips for printing and stacking finished envelopes. However, the exact configuration of each mailing machine is particular to the needs of the user. Customarily, the mailing machine also includes a transport apparatus, which feeds the envelopes in a path of travel through the successive modules of the mailing machine.
Generally, mailing machines are constructed depending upon the throughput characteristics, measured in a number of envelopes processed per minute, desired by the customer. To meet such diverse requirements, a wide range of mailing machines are commonly available. High throughput mailing machines tend to automate more of the envelope handling activities than low throughput mailing machines. As a result, mailing machines tend to be either hand fed or machine fed. In hand fed mailing machines, an operator places a single envelope along a feed deck until the envelope activates a trip switch and is engaged by the transport apparatus. In contrast, in machine fed mailing machines, the operator places a stack of envelopes on the feed deck and a pre-feed mechanism advances the stack into engagement with a singulator that separates the envelopes and delivers them seriatim (one at a time) to the transport apparatus.
Oftentimes, the moistener module is located within the mailing machine that is outside the control of the operator. In machine fed mailing machines, the moistener module is located downstream in the path of travel from the singulator because the flap of the envelope cannot be separated from the body of the envelope, wetted and sealed while the envelope is in the stack. Several examples of moistener modules that are located downstream of the singulator are shown in U.S. Pat. Nos. 4,971,686 and 5,138,816. In some hand fed mailing machines, such as those of U.S. Pat. Nos. 3,859,955, 4,450,037, 4,643,123, 4,775,143, 5,006,194 and 5,569,327, the moistener module is located downstream from the nip of the transport apparatus. As a result, the moistener module of both of these types of mailing machines is completely automated and operator intervention in this area is not allowed. Although such systems work generally well, they are very complex, costly to produce and do not handle a full spectrum of envelope shapes/sizes and flap profiles.
Hand fed mailing machines where the moistening/sealing function is not fully automated also exist. In U.S. Pat. No. 5,385,627, two feed paths are provided for. If the operator wants to seal the envelope (24), then it is hand feed along deck (18) so that the top edge (62) of the envelope is registered up against the fence (60) and the envelope passes underneath guide (136) so as to come into contact with the flap deflecting structure (80) before reaching the impression roller (70). On the other hand, if the operator does not want to seal the envelope (24), then it is hand feed along the top of the guide (136) so as to bypass the flap deflecting structure (80). Although this system works generally well, it suffers from various disadvantages. First, it requires considerable dexterity and skill on the part of the operator. The operator must select the correct path and then both advance and maintain proper registration of the envelope. Second, this arrangement does not provide the operator with tactile feedback that the flap has been separated properly. Third, at least one of the paths bends the envelope considerably increasing the risk of damage to the contents of the envelope and drag which requires greater motor torque to move the envelope through the machine.
U.S. Pat. Nos. 4,903,633, 4,926,787, 5,022,953 and 5,746,881 show another type of hand fed mailing machine where the moistening/sealing function is not fully automated. In these systems, to effect sealing the operator is required to manually separate the flap (72) from the body of the envelope (20) and place the flap in the gap 100 between the fence (50) and the deck (14A). On positioned in this manner, the envelope is advanced along the deck while maintaining the envelope""s top edge (52) against the fence. If no sealing is required, then the flap is not placed in the gap and the envelope is fed along the deck. Although this system has one fed path, it still suffers from various disadvantages. Here again, it requires considerable dexterity and skill on the part of the operator. The operator must simultaneously separate the flap, align the top edge with the fence and advance the envelope. Also, this technique is not intuitive and therefore inexperienced operators have difficulty producing properly sealed envelopes.
Therefore, there is a need for a cost effective hand fed mailing machine including a moistener assembly that is easier for operators to use and provides greater tactile feedback so that envelopes are properly sealed.
Accordingly, it is an object of the present invention to provide an improved mailing machine that addresses those issues described above. In accomplishing this and other objects there is provided a mailing machine including a base, a registration wall and a stripper blade. The base includes a deck defining a deck plane along which an envelope having an envelope body, an envelope flap and a top edge may be fed in a path of travel. The registration wall is located substantially perpendicular to the deck and parallel to the path of travel and along which the envelope top edge may be aligned during feeding. The stripper blade is located upstream in the path of travel from the deck, the stripper blade including a knife edge that is raised above the deck plane for separating the envelope flap from the envelope body.
Therefore, it should now be apparent that the invention substantially achieves the objects discussed above. Additional objects and advantages of the invention will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. Moreover, the objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.